CN117587656A

CN117587656A - ASA papermaking sizing emulsion, and preparation method and application thereof

Info

Publication number: CN117587656A
Application number: CN202311686181.3A
Authority: CN
Inventors: 郭志宇; 侯鲲; 孟鑫; 周晓园; 闫武军; 刘梦琦
Original assignee: JIANGSU FEYMER TECHNOLOGY CO LTD
Current assignee: JIANGSU FEYMER TECHNOLOGY CO LTD
Priority date: 2023-12-11
Filing date: 2023-12-11
Publication date: 2024-02-23

Abstract

The invention discloses an ASA papermaking sizing emulsion, a preparation method and application thereof, and belongs to the field of papermaking additives. The coating comprises the following components in parts by weight: 1.75 parts of 3.5wt% cationic starch solution; 5.25 parts of 1.5wt% of an amphoteric polyacrylamide solution; 0.01 part of surfactant; 1 part of ASA stock solution; and the D90 particle size of the sizing emulsion is 0.5-5.0um and/or the average particle size is 0.5-3.0um. According to the invention, cationic starch and amphoteric PAM are mixed according to a certain proportion, and react under specific conditions to prepare ASA emulsified mixed solution, so that the stability of the prepared emulsion is obviously improved, and particularly, the stability of the emulsion in a low-temperature environment is obviously better than that of the emulsion emulsified by a pure cationic starch emulsifier; and the prepared ASA emulsion can be used for different slurries of each layer, and meets the field use requirement.

Description

ASA papermaking sizing emulsion, and preparation method and application thereof

Technical Field

The invention belongs to the field of papermaking additives, and particularly relates to an ASA papermaking sizing emulsion, a preparation method and application thereof.

Background

ASA (alkenyl succinic anhydride) is a reactive neutral sizing agent commonly used in papermaking and is increasingly favored because of its rapid curing characteristics and wet heat stability. The curing rate of the ASA sizing lower machine is more than 80%, the AKD sizing is less than 50%, the sizing curing rate of the rosin size is dependent on the addition amount of aluminum sulfate in the system, and a large amount of aluminum sulfate enables the paper machine system to be in an acidic environment, so that calcium carbonate addition is not facilitated, and inorganic sediment of the paper machine system which is hard to clean is easily caused. ASA sizing thus has its unique advantages. The ASA stock solution is amber oily liquid, is insoluble in water, cannot be added uniformly in water environment, and can be dispersed in the water environment after being emulsified into an oil-in-water emulsion under the condition of an emulsifying agent, so that the ASA stock solution is used for a papermaking system. ASA must be prepared by emulsification in situ because of its high chemical reactivity and easy hydrolysis to form a dibasic acid hydrolysate that impedes sizing.

The on-site preparation method and process of the ASA emulsion directly affect the use effect of the ASA emulsion, and the stability and affinity of the emulsion directly affect the ASA sizing effect, so that the selection of the emulsifier is important except for a mature and stable emulsification process. Currently, ASA emulsifiers commonly used are natural polymeric emulsifiers (cationic starch) and synthetic polymeric emulsifiers (CPAM). Three commonly accepted emulsifying agents (cationic starch, polyglutaldehyde grafted modified polyacrylamide, which is hereinafter referred to as GPAM and amphoteric polyacrylamide (AM-DMC-DADMAC-AAS copolymerization, which is hereinafter referred to as amphoteric PAM)) have advantages and disadvantages: the cationic starch emulsifier has super-strong fiber selectivity affinity performance due to the similarity of the cationic starch emulsifier and fiber structure, has a certain resistance effect on ash and other system garbage, is generally used for high-filled cultural paper, and GPAM and amphoteric PAM have emulsifying ASA performance, and have outstanding performance under a low ash content high anion garbage system due to the use portability without cooking, high stability of emulsion, high anion garbage shielding performance and the like, so that the cationic starch emulsifier is widely used as an ASA emulsifier for a packaging paper system. However, the molecular chain characteristics are very easy to be adsorbed by filler particles such as calcium carbonate, so that the use effect is poor and the use is rarely performed in a high ash environment.

For multi-pulp papermaking systems such as coated white board paper, gray board paper and the like, the surface layer is a cultural paper papermaking system with high filler participation, the lining layer is a newsprint papermaking system with deinked pulp participation, the core bottom layer is a packaging paper papermaking system with OCC pulp participation, the traditional single-emulsifier emulsified ASA system cannot be simultaneously applied to multi-pulp papermaking systems such as coated white board paper, gray board paper and the like, the surface lining layer is generally sized by AKD, and the core bottom layer is sized by ASA. Because of the significant advantages in ASA sizing costs, customers prefer ASA sizing systems, there is a need for an ASA sizing system that can be used in a multi-stock papermaking system simultaneously to meet the stringent customer needs.

Disclosure of Invention

In order to overcome the technical defects, the invention provides an ASA papermaking sizing emulsion, a preparation method and application thereof, and aims to solve the problems related to the background technology.

The invention provides an ASA papermaking sizing emulsion, which comprises the following components in parts by weight:

and the D90 particle size of the sizing emulsion is 0.5-5.0um and/or the average particle size is 0.5-3.0um.

Preferably or alternatively, the alkenyl succinic anhydride stock solution is a mixture of 30-50wt% C196 alkenyl succinic anhydride and 50-70wt% C18 alkenyl succinic anhydride.

Preferably or optionally, the cationic starch is one or more of corn starch, tapioca starch and potato starch, which are subjected to cationic etherification treatment.

Preferably or alternatively, the cationic starch has a degree of substitution of greater than 0.025%.

Preferably or alternatively, the amphoteric polyacrylamide is a copolymer of any two or more monomers selected from acrylamide, methacryloxyethyl trimethyl ammonium chloride, dimethyl diallyl ammonium chloride, acrylic acid and salts thereof, methacrylic acid and salts thereof.

Preferably or alternatively, the molecular weight of the amphoteric polyacrylamide is 200000-1000000.

Preferably or alternatively, the surfactant comprises one or more of alkyl alcohol polyether phosphate, fatty alcohol polyoxyethylene ether phosphate salt, fatty alcohol amide phosphate, fatty acid sulfonate, saturated alcohol ether sulfonate, sulfosuccinate and the like.

The invention also provides a preparation method of the ASA papermaking sizing emulsion, which comprises the following steps:

the cationic starch solution and the amphoteric polyacrylamide solution are mixed according to the following ratio of 1: preparing a mixed solution according to a mass ratio of 1 to 1:5, adding a surfactant, and adjusting pH to be slightly acidic;

the ASA stock solution and the mixed solution are mixed according to the mass ratio of 1:5 to 1:9, and then are sheared and emulsified in a shearing machine, and the D90 particle size of the sizing emulsion is regulated to be 0.5-5.0um and/or the average particle size is regulated to be 0.5-3.0um.

Preferably or alternatively, the rotational speed of the shears is 10000rpm; the emulsification time was 90s.

The invention also provides application of the ASA papermaking sizing emulsion in preparing papermaking.

The invention relates to an ASA papermaking sizing emulsion, a preparation method and application thereof, which have the following beneficial effects compared with the prior art: according to the invention, cationic starch and amphoteric PAM are mixed according to a certain proportion, and react under specific conditions to prepare ASA emulsified mixed solution, so that the stability of the prepared emulsion is obviously improved, and particularly, the stability of the emulsion in a low-temperature environment is obviously better than that of the emulsion emulsified by a pure starch emulsifier;

moreover, the application effect of the prepared emulsion is obviously better than that of the emulsion emulsified by a single emulsifier; the self-adsorption capacity of the emulsion is obviously better than that of the emulsion emulsified by a single emulsifier, the dependence on the retention aid is obviously reduced, and the high-efficiency application effect can be still maintained under the environment of insufficient addition of the retention aid; the universality is obviously improved, the ASA emulsion prepared by the method can be simultaneously applied to high calcium carbonate filling paper and packaging paper, such as coated white board paper, gray board paper and the like, and can be applied to different slurries of each layer to meet the field use requirement.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the invention may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the invention.

Summary of The Invention

The traditional ASA emulsification sizing method is to dilute cationic starch or polymer emulsifier to a certain concentration, adjust pH, mix with ASA, high-speed shear by an emulsification pump to emulsify ASA stock solution into ASA emulsion with a certain average particle size or median particle size, dilute for the second time, add into a paper pulp system, and make and shape paper after drying to have a certain water resistance.

The invention effectively combines the advantages of cationic starch and polymer emulsifier, so that the emulsion has the advantages of improved stability, more excellent low-temperature resistance, reduced dependence on retention aid, better universality and the like, and particularly in multi-pulp systems such as ash base white board and the like, one set of ASA sizing system is generally applicable to each layer of pulp, and the sizing performance is obviously improved. The specific preparation method comprises the following steps: preparing a mixed solution of starch solution and amphoteric Polyacrylamide (PAM) solution in a specific proportion, adding a certain special surfactant, adjusting pH to be weak acid, mixing with ASA in a specific proportion, shearing and emulsifying in a shearing machine at a high speed, adjusting to a specified particle size distribution, diluting, and adding into a slurry system.

Wherein, the higher the substitution degree of the cationic starch, the smaller the particle size of the emulsion and the better the adsorptivity of the emulsion and the fiber, but the technology and the cost are limited, and the substitution degree of the cationic starch is generally between 0.025 and 0.07 percent.

The invention is further illustrated below in conjunction with examples, examples of which are intended to illustrate the invention and are not to be construed as limiting the invention.

Example 1:

the cooked 3.5% cationic starch solution (the substitution degree of the cationic starch is 0.034%, the same applies to the following examples) was cooled to about 50 ℃, 175g was weighed into an emulsifying tank, the pH was adjusted to 4.0 with 10% citric acid, 25g ASA stock solution was added, shearing was stopped at 10000RPM for 90S, and ASA emulsion concentrate (the alkenyl succinic anhydride stock solution was a mixture of 30% by weight of C16 alkenyl succinic anhydride and 70% by weight of C18 alkenyl succinic anhydride, the same applies to the following examples) was obtained. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 2:

175g1.5% effective content of amphoteric PAM is weighed into an emulsifying tank, pH is regulated to 4.0 by 10% citric acid, 25g ASA stock solution is added, shearing is carried out at high speed for 90S under 10000RPM condition, and shearing is stopped, thus obtaining ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2 or test example 3.

Example 3:

29.2g of 3.5% cationic starch solution and 145.8g of 1.5% amphoteric PAM solution are weighed, evenly mixed and stirred, the pH value is regulated to 4.0 by 10% citric acid under the stirring state, the mixture is fully stirred and reacted for 10min, 25g of ASA stock solution is added, the mixture is sheared for 90S at high speed under 10000RPM condition, and the shearing is stopped to obtain ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2 or test example 3.

Example 4:

weighing 43.75g of 3.5% cationic starch solution and 131.25g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 4.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 5:

and (3) weighing 87.5g of 3.5% cationic starch solution, mixing and stirring uniformly with 87.5g of 1.5% amphoteric PAM solution, regulating the pH to 4.0 with 10% citric acid under stirring, stirring for fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 6:

weighing 131.25g of 3.5% cationic starch solution and 43.75g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 4.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 7:

weighing 145.8g of 3.5% cationic starch solution and 29.2g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 4.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 8:

weighing 43.75g of 3.5% cationic starch solution and 131.25g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 3.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2. Example 9:

weighing 43.75g of 3.5% cationic starch solution and 131.25g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 5.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 10:

weighing 43.75g of 3.5% cationic starch solution and 131.25g of 1.5% amphoteric PAM solution, uniformly mixing and stirring, regulating the pH to 6.0 with 10% citric acid under stirring, fully reacting for 10min, adding 25g of ASA stock solution, shearing at high speed for 90S under 10000RPM condition, and stopping shearing to obtain ASA emulsified concentrate. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 11:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, evenly mixed and stirred, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is fully stirred and reacted for 10 minutes, 0.125g of alkyl phosphate is added, 25g of ASA stock solution is added, the mixture is sheared for 90 seconds at high speed under 10000RPM condition, and the shearing is stopped, so that ASA emulsified concentrated solution is obtained. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 12:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, evenly mixed and stirred, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is fully stirred and reacted for 10 minutes, 0.125g fatty alcohol polyoxyethylene ether phosphate (salt) is added, 25g ASA stock solution is added, high-speed shearing is carried out for 90S under 10000RPM condition, and shearing is stopped, thus obtaining ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 13:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, mixed and stirred uniformly, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is stirred fully and reacted for 10 minutes, 0.125g fatty alcohol amide phosphate is added, 25g ASA stock solution is added, high-speed shearing is carried out for 90S under 10000RPM condition, and shearing is stopped, thus obtaining ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 14:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, mixed and stirred uniformly, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is stirred fully and reacted for 10 minutes, 0.125g of sulfosuccinate is added, 25g of ASA stock solution is added, high-speed shearing is carried out for 90S under 10000RPM condition, and shearing is stopped, thus obtaining ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 15:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, evenly mixed and stirred, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is fully stirred and reacted for 10 minutes, 0.025g of fatty alcohol polyoxyethylene ether phosphate is added, 25g of ASA stock solution is added, the mixture is sheared for 90 seconds at high speed under 10000RPM condition, and the shearing is stopped, so that ASA emulsified concentrated solution is obtained. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Example 16:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, mixed and stirred uniformly, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is stirred fully and reacted for 10 minutes, 0.25g of fatty alcohol polyoxyethylene ether phosphate is added, 25g of ASA stock solution is added, high-speed shearing is carried out for 90S under 10000RPM condition, and shearing is stopped, thus obtaining ASA emulsified concentrated solution. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2 or test example 3.

Example 17:

3.5 percent cationic starch solution 43.75g and 1.5 percent amphoteric PAM solution 131.25g are weighed, evenly mixed and stirred, the pH value is regulated to 7.0 by 10 percent citric acid under the stirring state, the mixture is fully stirred and reacted for 10 minutes, 0.375g of fatty alcohol polyoxyethylene ether phosphate is added, 25g of ASA stock solution is added, the mixture is sheared for 90 seconds at high speed under 10000RPM condition, and the shearing is stopped, so that ASA emulsified concentrated solution is obtained. The particle size and stability of the concentrate were measured by the method of test example 1, and the sizing degree was measured by the method of test example 2.

Detection example 1

The test example provides an evaluation method for evaluating the particle size distribution and emulsion stability of ASA sizing emulsion in a laboratory, wherein the test results are shown in Table 1, and the detection parameters and the detection method are as follows:

1. particle size distribution: the particle size distribution of the emulsion concentrate obtained in examples 1 to 17 was measured by using a HORIBA LA-300 particle size distribution analyzer, and the D90% particle size (particle size corresponding to the number of cumulative particle size distributions of one sample reaching 90%) and the mean particle size were recorded;

2. emulsion stability: the emulsion concentrates prepared in examples 1 to 17 were filled into glass bottles, and the test method of the particle size distribution of test example 1 was used to examine whether the emulsion was broken or flocculated or delaminated by preserving at a constant temperature of 40℃for 2 hours for short-term stability (particle size and emulsion state) and preserving at a constant temperature of 40℃for 6 hours and at a constant temperature of 25℃for 30 days for long-term stability (emulsion state).

Detection example 2

The test example provides an evaluation method for evaluating the water resistance of ASA emulsion sizing by a laboratory simulated on-site papermaking system, the test results are shown in Table 2, and the detection parameters and the detection method are as follows:

1. the ASA concentrate was diluted 100-fold with tap water (conductivity 300 us/cm) for use.

2. Respectively taking the slurry which is coated on site and is not added with ASA sizing agent after a surface layer (cultural pulp system, 50% poplar machine pulp, 25% bleached sulfate hardwood pulp, 10% bleached sulfate softwood pulp, 15% office waste pulp, calcium carbonate filler PCC-30%), a core layer (newsprint pulp system, 100% DIP pulp) and a bottom layer (packaging paper pulp system, 100% OCC pulp) are subjected to pulp flushing pump, weighing each layer of slurry according to the quantitative pulping of 100g/m < 2 >, putting the slurry into a beaker, adding the ASA secondary diluted emulsion (3.0 kg of surface layer ton pulp, 2.0kg of core layer ton pulp and 0.5kg of bottom layer ton pulp) prepared in the step of (1), stirring for 30S, adding vast-rich retention aid VD8240 of 0.25kg of ton paper, continuously stirring for 60S, transferring to a sheet making paper sheet by a sheet making machine, drying for 6min in a paper dryer at 95 ℃ after pressing, and keeping constant temperature and humidity for 24H.

3. The sizing degree of the paper sample is tested by adopting the national standard method GBT 5405-2002 paper sizing degree measurement (liquid permeation method).

Detection example 3

The test example provides an evaluation method for evaluating the water resistance of ASA emulsion sizing by a laboratory simulated on-site papermaking system (the difference of the test example relative to the test example 2 is that the ratio of ASA emulsion to retention aid VD 8240) and the test result is shown in the table 2, and the detection parameters and the detection method are as follows:

2. Respectively taking the slurry which is coated on site and is not added with ASA sizing agent after a surface layer (cultural pulp system, 50% poplar machine pulp, 25% bleached sulfate hardwood pulp, 10% bleached sulfate softwood pulp, 15% office waste pulp, calcium carbonate filler PCC-30%), a core layer (newsprint pulp system, 100% DIP pulp) and a bottom layer (packaging paper pulp system, 100% OCC pulp) are subjected to pulp flushing pump, weighing each layer of slurry according to the quantitative pulping of 100g/m < 2 >, putting the slurry into a beaker, adding the ASA secondary diluted emulsion (3.0 kg of surface layer ton pulp, 2.0kg of core layer ton pulp and 0.5kg of bottom layer ton pulp) prepared in the step of (1), stirring for 30S, adding vast-rich retention aid VD8240 of 0.1kg of ton paper, continuously stirring for 60S, transferring to a sheet making paper sheet by a sheet making machine, drying for 6min in a paper dryer at 95 ℃ after pressing, and keeping constant temperature and humidity for 24H.

Table 1: particle size distribution and emulsion stability Properties of the ASA sizing emulsions obtained in examples 1 to 17

Table 2: sizing Water resistance of ASA sizing emulsions obtained in examples 1 to 17

Discussion:

from the data in table 1, it can be seen that: by adopting the examples 12 to 17 to mix starch and amphoteric PAM according to a certain proportion and adding the surfactant, the product can be used for emulsifying ASA stock solution by using the emulsifying agent, and the stability of the prepared emulsion is obviously improved, especially the stability under low-temperature environment is obviously better than that of the emulsion emulsified by using the pure starch emulsifying agent. In comparative examples 11 to 17, the addition of the fatty alcohol-polyoxyethylene ether phosphate surfactant in a specific ratio can make the particle size of the emulsified ASA stock solution smaller and the stability better. Comparative example 1, examples 8 to 10, the reaction product was most effective for emulsifying ASA when starch was mixed with amphoteric PAM in a weakly acidic environment, specifically at a pH of 4.0 to 6.0. In particular, the ASA emulsion dilutions prepared in example 16 and example 17 have small initial particle size and good stability, and the emulsion state is stable for 30 days.

From the data in table 2, it can be seen that: the emulsion prepared by adopting the method has obviously increased universality, can be simultaneously applied to high-calcium carbonate filling paper and packaging paper, such as coated white board paper, gray board white board paper and the like, and the ASA emulsion prepared by adopting the method can be applied to different slurries of each layer to meet the field use requirement. The emulsions prepared by the present invention are significantly better in application than emulsions emulsified with a single emulsifier as compared to examples 1, 2, and 6. The self-adsorption capacity of the emulsion prepared by the method is obviously better than that of the emulsion emulsified by the single emulsifier in the embodiment, the dependence on the retention aid is obviously reduced, and the high-efficiency application effect can be still maintained under the environment of insufficient addition of the retention aid; in particular, the ASA emulsion prepared in example 16 was applied to paper with significantly better water resistance than the other examples, and the emulsion had stable application properties with significantly less dependence on the retention aid.

In conclusion, the high polymer substance emulsified ASA emulsion prepared by the invention has the following properties: the stability of the ASA emulsion in a low-temperature environment is improved, the dependence on retention aids in the sizing process is reduced, the ASA emulsion sizing effect is improved, and the method is completely suitable for multi-pulp papermaking systems such as coated white board paper ash bottom white board paper and the like.

In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. The various possible combinations of the invention are not described in detail in order to avoid unnecessary repetition.

Claims

1. The ASA papermaking sizing emulsion is characterized by comprising the following components in parts by weight:

2. ASA papermaking sizing emulsion according to claim 1, characterized in that the alkenyl succinic anhydride stock solution is a mixture of 30-50wt% of C16 alkenyl succinic anhydride and 50-70wt% of C18 alkenyl succinic anhydride.

3. The ASA papermaking sizing emulsion of claim 1, wherein the cationic starch is one or more of corn starch, tapioca starch and potato starch, which are subjected to cationic etherification treatment.

4. The ASA papermaking sizing emulsion of claim 3, wherein the cationic starch has a degree of substitution greater than 0.025%.

5. The ASA papermaking sizing emulsion of claim 1, wherein the amphoteric polyacrylamide is a copolymer of any two or more monomers from the group consisting of acrylamide, methacryloxyethyl trimethyl ammonium chloride, dimethyl diallyl ammonium chloride, acrylic acid and salts thereof, methacrylic acid and salts thereof.

6. ASA papermaking sizing emulsion according to claim 5, characterized in that the molecular weight of the amphoteric polyacrylamide is 200000-1000000.

7. The ASA papermaking sizing emulsion of claim 1, wherein the surfactant comprises one or more of alkyl alcohol polyether phosphate, fatty alcohol polyoxyethylene ether phosphate, fatty alcohol amide phosphate, fatty acid sulfonate, saturated alcohol ether sulfonate, sulfosuccinate.

8. The preparation method of the ASA papermaking sizing emulsion is characterized by comprising the following steps of:

the cationic starch solution and the amphoteric polyacrylamide solution are mixed according to the following ratio of 1: preparing a mixed solution according to a mass ratio of 1 to 1:5, adding a surfactant, and adjusting the pH to be slightly acidic, wherein the pH is preferably 4-6;

mixing ASA stock solution and mixed solution according to a mass ratio of 1:5 to 1:9, shearing and emulsifying in a shearing machine, and adjusting the D90 particle size of the sizing emulsion to be 0.5-5.0um and/or the average particle size to be 0.5-3.0um.

9. The method of preparing an ASA papermaking sizing emulsion according to claim 8, wherein the rotational speed of the shear is 8000-12000rpm; the emulsification time is 60-120s.

10. Use of a sizing emulsion for ASA paper manufacture according to any of claims 1 to 7 for the preparation of paper.